BACKGROUND
1. Field of the Invention
The present invention relates to a power supply circuit on a motherboard.
2. Description of Related Art
The motherboard of a typical computer consists of a large printed circuit board. It holds electronic components, as well as physical connectors (sockets, slots, and headers) into which other electronic components may be inserted or attached. When the motherboard is boot-strapped, the system power supplies power to all the electronic components on the motherboard.
But not all of the electronic components on the motherboard need to be on all the time, given that they constantly consume power.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of the first embodiment of a power supply circuit on a motherboard in accordance with the present invention;
FIG. 2 is block diagram of the second embodiment of a power supply circuit on a motherboard in accordance with the present invention;
FIG. 3 is block diagram of the third embodiment of a power supply circuit on a motherboard in accordance with the present invention; and
FIG. 4 is block diagram of the fourth embodiment of a power supply circuit on a motherboard in accordance with the present invention.
DETAILED DESCRIPTION
Referring to FIG. 1, a power supply circuit on a motherboard in accordance with a first embodiment of the present invention includes a first switch apparatus such as a first jumper 10, and a first power control unit such as a first control chip 12. The first jumper 10 includes a first jumper power pin, a first jumper ground pin, and a first jumper control pin. The first jumper power pin is connected to a control-power source Vcc via a first resistor R1. The first jumper ground pin is grounded. The first control chip 12 includes a first control chip low-enable pin, a first control chip input pin, and a first control chip output pin. The first jumper control pin is connected to the first control chip low-enable pin to control status of the first control chip 12. The first control chip input pin is connected to a first work-power module 14. The first control chip output pin is connected to a first electronic component 16.
When the first jumper power pin is coupled to the first jumper control pin, the first jumper control pin outputs a high level voltage, the first control chip low-enable pin is at a TTL high level, and the first control chip 12 is turned off. Thereby, the first electronic component 16 is not on and does not receive power. When the first jumper ground pin is coupled to the first jumper control pin, the first jumper control pin outputs a low level voltage, the first control chip low-enable pin is at a TTL low level, and the first control chip 12 is turned on. Thereby, the first electronic component 16 is supplied power and is on and working. In other embodiments, the first control chip low-enable pin can be a first control chip high-enable pin. When the first jumper power pin is coupled to the first jumper control pin, the first electronic component 16 receives power. And when the first jumper ground pin is coupled to the first jumper control pin, the first electronic component 16 does not receive power.
Referring to FIG. 2, a power supply circuit on a motherboard in accordance with a second embodiment of the present invention includes a second switch apparatus such as a second jumper 20, and a second power control unit such as a P type Metallic Oxide Semiconductor Field Effect Transistor (P-MOSFET) Q. The second jumper 20 includes a second jumper power pin, a second jumper ground pin, and a second jumper control pin. The second jumper power pin is connected to the control-power source Vcc via a second resistor R2. The second jumper ground pin is grounded. The gate of Q is connected to the second jumper control pin. The drain of Q is connected to a second work-power module 22. The source of Q is connected to a second electronic component 24.
When the second jumper power pin is coupled to the second jumper control pin, the second jumper control pin outputs a high level voltage. The gate of Q is at a TTL high level, and Q is turned off. Thereby, the second electronic component 24 does not receive power. When the second jumper ground pin is coupled to the second jumper control pin, the second jumper control pin outputs a low level voltage. The gate of Q is at a TTL low level, and Q is turned on. Thereby, the second electronic component 24 receives power.
Referring to FIG. 3, a power supply circuit on a motherboard in accordance with a third embodiment of the present invention includes a third switch apparatus such as a third jumper 30, a fourth switch apparatus such a fourth jumper 31, a third power control unit such as a second control chip 32, and a fourth power control unit such as a third control chip 33. The third jumper 30 includes a third jumper power pin, a third jumper ground pin, and a third jumper control pin. The fourth jumper 31 includes a fourth jumper power pin, a fourth jumper ground pin, and a fourth jumper control pin. The third jumper power pin is connected to the control-power source Vcc via a third resistor R3. The fourth jumper power pin is connected to the control-power source Vcc via a fourth resistor R4. The third jumper ground pin and the fourth jumper ground pin are both grounded. The second control chip 32 includes a second control chip input pin, a second control chip output pin, and a second control chip low-enable pin. The third control chip 33 includes a third control chip input pin, a third control chip output pin, and a third control chip low-enable pin. The second control chip low-enable pin is connected to the third jumper control pin. The second control chip output pin is connected to a third electronic component 36. The second control chip input pin is connected to a third work-power module 34 with a first voltage. The third control chip low-enable pin is connected to the fourth jumper control pin. The third control chip output pin is connected to the third electronic component 36. The third control chip input pin is connected to a fourth work-power module 35 with a second voltage.
When the third jumper power pin is coupled to the third jumper control pin, and the fourth jumper ground pin is coupled to the fourth jumper control pin, the third jumper control pin outputs a high level voltage, and the fourth jumper control pin outputs a low level voltage. The second control chip low-enable pin is at a TTL high level, and the third control chip low-enable pin is at a TTL low level, so the second control chip 32 is turned off, and the third control chip 33 is turned on. Thereby, the third electronic component 36 receives the second voltage. When the third jumper ground pin is coupled to the third jumper control pin, and the fourth jumper power pin is coupled to the fourth jumper control pin, the third jumper control pin outputs a low level voltage, and the fourth jumper control pin outputs a high level voltage. The second control chip low-enable pin is at a TTL low level, and the third control chip low-enable pin is at a TTL high level, so the second control chip 32 is turned on, and the third control chip 33 is turned off. Thereby, the third electronic component 36 receives the first voltage. When the third jumper power pin is coupled to the third jumper control pin, and the fourth jumper power pin is coupled to the fourth jumper control pin, the third electronic component 36 does not receive any voltage.
In other embodiments, the second and third control chips 32, 33 can be replaced by two P-MOSFETs. The gates of the two P-MOSFETs are respectively connected to the third and fourth jumper control pins. The drains of the two P-MOSFETs are respectively connected to the third and fourth jumper power modules 34, 35. The sources of the two P-MOSFET Transistors are both connected to the third electronic component 36.
When the third jumper power pin is coupled to the third jumper control pin, and the fourth jumper ground pin is coupled to the fourth jumper control pin, the P-MOSFET Transistor which is connected to the third control chip 32 is turned off, and the P-MOSFET Transistor which is connected to the fourth control chip 33 is turned on. Thereby, the third electronic component 36 receives the second voltage. When the third jumper ground pin is coupled to the third jumper control pin, and the fourth jumper power pin is coupled to the fourth jumper control pin, the P-MOSFET Transistor, which is connected to the third control chip 32 is turned on, and the P-MOSFET Transistor which is connected to the fourth control chip 33 is turned off. Thereby, the third electronic component 36 receives the first voltage. When the third jumper power pin is coupled to the third jumper control pin, and the fourth jumper power pin is coupled to the fourth jumper control pin, the two P-MOSFET Transistors are both turned off. Thereby, the third electronic component 36 does not receive any voltage.
Referring to FIG. 4, a power supply circuit on a motherboard in accordance with a third embodiment of the present invention includes a fifth switch apparatus such as a fifth jumper 40, a sixth switch apparatus such a sixth jumper 41, a fifth power control unit such as a fourth control chip 42, and a sixth power control unit such as a fifth control chip 43. The fifth jumper 40 includes a fifth jumper power pin, a fifth jumper control pin, and a fifth jumper ground pin. The sixth jumper 41 includes a sixth jumper power pin, a sixth jumper control pin, and a sixth jumper ground pin. The fifth and sixth jumper power pins are connected to the control-power source Vcc respectively via a fifth resistor R5 and a sixth resistor R6. The fifth and sixth jumper ground pins are both grounded. The fourth control chip 42 includes a fourth control chip low-enable pin, a fourth control chip input pin, and a fourth control chip output pin. The fifth control chip 43 includes a fifth control chip low-enable pin, a fifth control chip input pin, and a fifth control chip output pin. The fourth and fifth control chip low-enable pins are respectively connected to the fifth jumper control pin and the sixth jumper control pin. The fourth and fifth control chip input pins are both connected to a share-work-power module 44. The fourth and fifth control chip output pins are respectively connected to a fourth electronic component 45 and a fifth electronic component 46. When the fifth jumper power pin is coupled to the fifth jumper control pin, the fourth electronic component 45 does not receive power. When the fifth jumper ground pin is coupled to the fifth jumper control pin, the fourth electronic component 45 receives power. When the sixth jumper power pin is coupled to the sixth jumper control pin, the fifth electronic component 46 does not work. When the sixth jumper ground pin is coupled to the sixth jumper control pin, the fifth electronic component 46 receives power.
In other embodiments, the fourth, fifth control chips 43 and 44 can be replaced by two P-MOSFET Transistors. The two gates of the two P-MOSFET Transistors are respectively connected to the fifth and the sixth jumper control pins. The two drains of the two P-MOSFET Transistors are both connected to the share-work-power module 44. The two sources of the two P-MOSFET Transistors are respectively connected to the fourth, fifth electronic components 45 and 46.
When the fifth jumper power pin is coupled to the fifth jumper control pin, the fourth electronic component 45 does not receive power. When the fifth jumper ground pin is coupled to the fifth jumper control pin, the fourth electronic component 45 receives power. When the sixth jumper power pin is coupled to the sixth jumper control pin, the fifth electronic component 46 does not receive power. When the sixth jumper ground pin is coupled to the sixth jumper control pin, the fifth electronic component 46 receives power.
In other embodiments, the P-MOSFET Transistors can be replaced by N-MOSFET Transistors. The jumpers can be replaced by other elements, such as switches with two throws. A first switch pin of one of the switches is connected to the control-power source Vcc. A second switch pin of one of the switches acts as a jumper control pin. A third switch pin of one of the switches is grounded.
The power supply circuit on a motherboard can supply power to each electronic component individually. When one of the electronic components on the motherboard is not working, the power supply circuit stops supplying power to the electronic component, and it saves power.
The foregoing description of the exemplary embodiments of the invention has been presented only for the purposes of illustration and description and is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to explain the principles of the invention and their practical application so as to enable others skilled in the art to utilize the invention and various embodiments and with various modifications as are suited to the particular use contemplated. Alternately embodiments will become apparent to those skilled in the art to which the present invention pertains without departing from its spirit and scope. Accordingly, the scope of the present invention is defined by the appended claims rather than the foregoing description and the exemplary embodiments described therein.